The hubbub about Beyoncé’s “to lip synch or not” performance of the national anthem at Obama’s second inauguration aside, everyone I’ve spoken with and read LOVED her performance. Soul superstar Aretha Franklin told ABC News that Beyoncé “did a beautiful job.” Spin Magazine called her rendition “Amazing.” Musically, however, Beyoncé’s Banner presents an unmentioned and rather profound expressive reworking of the song. It also offers a salute to one of the Banner’s most praised performers and performances—the late Whitney Houston and her 1991 Super Bowl rendition.

Meter is one of the fundamental parameters of musical (and poetic) expression. It concerns the organization of musical pulses into groupings. The most basic contrast is between duple and triple time–that is between music with groups of even numbers of beats or groupings by three. The waltz is the emblematic triple-time dance and the waltz’s lilting, flowing sense of movement is produced by dancers transcending the mismatch of two feet moving against three beats. Triple time tends to add extra emphasis or weight to the beginning of each grouping and all told is the more rare meter. Duple meter is more common and is typical of the march and the vast majority of instrumental music, much of which also extends from the world of dance but here two feet match each set of two beats allowing for a regular right – left symmetry.

“The Star-Spangled Banner,” however, is one of those rarer triple time songs, originally notated in 6/4 time and more usually today in 3/4. Yet some of the Banner’s more celebrated recent performances are arranged in a slow duple meter. This is a pretty radical change, expressively.

The anthem’s triple time connects to the energetic patter of the original song, which of course borrowed the melody and affect of a rollicking British tune in joyful celebration of America’s surprise defeat of the powerful British fleet at the mouth of Baltimore Harbor. Since that day, the Banner has shifted meaning. No longer a topical party song, it is now a timeless expression of devotion to country. The tempo has slowed. The song has become sacred.

Adding a beat to each measure expands upon this newfound sacred resonance of the song as anthem. The 4/4 Banner swells to embody its role as national symbol. Beyoncé takes advantage of the meter change and its expressive power. She sings most of the song in 4/4/, drawing out the first syllable of each measure (now sounded over a half note or even a dotted half, rather than a quarter note). Her voice embraces each syllable as if in 4/4, the song becomes a more relaxed and spiritual love song of country.

The use of 4/4 time smooths out the downbeat bump of triple time and gives the singer more time (literally 33% more) to linger over the first word of each measure. Houston’s emblematic Super Bowl performance features the same transformation, but Beyoncé returns to the original triple time at the penultimate phrase: “O Say does that Star Spangled Banner yet wave,” adding momentum and urgency to the performance and setting up a dramatic contrast with a subsequent return to 4/4 time for an ecstatic climax on the final lyric “O’er the land of the free and the home of the brave.”

Whether the temperature was too cold or sound system too uncomfortable for Beyoncé to risk a live performance, Beyoncé’s intent was to offer an especially passionate and expressive performance of the nation’s Anthem. I can’t complain about the result.